Better test coverage for breaches API

breach_test.go

@@ -1,11 +1,19 @@
 package hibp
 
 import (
+	"encoding/json"
 	"fmt"
 	"os"
 	"testing"
 )
 
+const (
+	validDateJSON     = `{"date": "2022-10-01"}`
+	validNullDateJSON = `{"date": "null""}`
+	invalidJSON       = `{"date": '2022-10-01'}`
+	invalidDateJSON   = `{"date": "202299-10-01"}`
+)
+
 // TestBreaches tests the Breaches() method of the breaches API
 func TestBreaches(t *testing.T) {
 	hc := New()
@@ -238,6 +246,44 @@ func TestBreachedAccountWithoutTruncate(t *testing.T) {
 	}
 }
 
+// TestApiDate_UnmarshalJSON_Time tests the ApiDate type JSON unmarshalling
+func TestApiDate_UnmarshalJSON_Time(t *testing.T) {
+	type testData struct {
+		Date *ApiDate `json:"date"`
+	}
+	tt := []struct {
+		n   string
+		j   []byte
+		d   string
+		nil bool
+		sf  bool
+	}{
+		{"valid Date JSON", []byte(validDateJSON), "2022-10-01", false, false},
+		{"valid Null Date JSON", []byte(validNullDateJSON), "", true, false},
+		{"invalid JSON", []byte(invalidJSON), "", true, true},
+		{"invalid Date", []byte(invalidDateJSON), "", true, true},
+	}
+
+	for _, tc := range tt {
+		t.Run(tc.n, func(t *testing.T) {
+			var td testData
+			if err := json.Unmarshal(tc.j, &td); err != nil && !tc.sf {
+				t.Errorf("failed to unmarshal test JSON: %s", err)
+			}
+			if td.Date == nil && !tc.nil {
+				t.Errorf("unmarshal on ApiDate type failed. Expected data but got nil")
+				return
+			}
+			if !tc.nil {
+				tdd := td.Date.Time().Format("2006-01-02")
+				if tdd != tc.d && !tc.sf {
+					t.Errorf(`unmarshal of ApiDate type failed. Expected: %q, got %q"`, tc.d, tdd)
+				}
+			}
+		})
+	}
+}
+
 // ExampleBreachApi_Breaches_getAllBreaches is a code example to show how to fetch all breaches from the
 // HIBP breaches API
 func ExampleBreachApi_Breaches_getAllBreaches() {